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**我在运行时遇到错误，错误是因为包或其他原因，我已删除所有旧代码并添加新代码，但仍面临以下错误。

错误：“NavigationBar”是从“package:flutter/src/material/navigation_bar.dart”和“package:flutter_onboarding_slider/navigation_bar.dart”导入的。\nappBar: NavigationBar(\n^^^^^^^^^^ ^^^\n: 警告：空感知操作“?.”的操作数的类型为“GoogleMapController”，不包括空值。\nlib/\xe2\x80\xa6/map/map.dart:62

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• “GoogleMapController”来自“package:google_maps_flutter/google_maps_flutter.dart”(“/D:/flutter/.pub-cache/hosted/pub.dartlang.org/google_maps_flutter-2.1.7/lib/google_maps_flutter.dart”)。\ npackage:google_maps_flutter/google_maps_flutter.dart:1\n_controller?.animateCamera(CameraUpdate.newCameraPosition(CameraPosition(\n^

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  导入 'package:flutter/cupertino.dart';\n导入 'package:flutter/material.dart';\n导入 'package:flutter_onboarding_slider/flutter_onboarding_slider.dart';\n导入 'package:fyppedometer/mainScreens/Navigation/navigationBar.dart' ;\n导入 'package:fyppedometer/widgets/constants.dart';\n导入 'package:fyppedometer/widgets/text.dart';

  \n

  class MyHome 扩展 StatefulWidget {\nconst MyHome({Key? key}) : super(key: key);

  \n

  @override\nState<MyHome> createState() => _MyHomeState();\n

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  }

  \n

  class _MyHomeState extends State {\n最终颜色 kDarkBlueColor = Colors.cyan;

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  // ignore: non_constant_identifier_names\n\nList<String> numbers_Height = [\n  for (var i = 1.1; i <= 10.0; i = i + 0.1) i.toString()\n];\n// ignore: non_constant_identifier_names\nList<String> numbers_Weight = [for (var i = 1; i <= 1000; i++) …

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